Fujitsu F2MC-16LX Hardware Manual page 305

[bit 14] DRQOIE: Received data interruption permission bit
It allows an interrupt due to the interrupt factor for the EP0O status register "DRQO" to be generated.
DRQOIE
0
1
[bit 13] SPKIE: Short packet interruption permission bit
It allows an interrupt due to the interrupt factor for the EP0O status register "SPK" to be generated.
SPKIE
0
1
[bit 12, bit 11] Reserved bit
This bit is undefined at read. No effect on writing.
[bit 10] DRQO: Received data interrupt request bit
It indicates that OUT packet has been successfully transferred from the EP0 host, data has been written
into the receive buffer, and the receive data can be read from the buffer. The DRQO bit is an interrupt
factor and writing "1" is ignored. Please clear by writing "0". "1" is read at the read modification write.
DRQO
0
1
Note:
After the data read of reception buffer is processed, the DRQO must be cleared. Also, writing "0"
when the DRQO is not set is disabled. When the DRQO is set to "1", the reception buffer is not
updated. The buffer is enabled to update when it is cleared. When the OUT packet request is
executed with DRQO set "1", the NAK is responded to the HOST automatically.
[bit 9] SPK: Short packet interrupt request bit
It indicates that the number of pieces of transfer data that has been successfully received from the host
is less than a maximum number of packets set in PKS in the EP0 control register (EP0C) (including 0
byte). The SPK bit is a interrupt factor and writing "1" is ignored. Please clear by writing "0". "1" is
read at the read modification write.
SPK
0
1
Interrupt disabled by DRQO factor
Interruption permission by DRQO factor
Interrupt disabled by SPK factor
Interruption permission by SPK factor
Clearing interrupt cause
Reading receive data enable state
Maximum number of transfer packets received
Data less than the maximum number of transfer packets received
CHAPTER 13 USB FUNCTION
Operating mode
Operating mode
Operating mode
Operating mode
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